In this paper, we extend our previous work on the discrete time state space aeroelastic modeling technique using FUN3D further for the gust analysis. We have utilized a subspace realization algorithm to identify the individual aerodynamic sub-systems, i.e., due to the structural deformations (modal coordinates), control surface deflections, respectively. The dataset needed for the aerodynamic system identifications are obtained by a wrapper program, called OVERFUN, driving the underlying FUN3D solver. In current work, a generalized table format gust input is implemented for FUN3D so that the random gust profile can be utilized. Efficiency of the table look up algorithm for the computation of gust velocity at each CFD grid is carefully addressed. The sectional/component loads are included as a part of the system outputs in addition to the generalized aerodynamic forces during the aerodynamic sub-system identification, thus the final assembled aeroelastic state space model is enabled with component load monitoring capability. A normalization and de-normalization procedure is implemented to the system identification algorithm to circumvent potential numerical issues associated with the different levels of amplitudes of the system inputs/outputs. Numerical results for the Goland wing configuration at two Mach numbers 0.85 and 0.94 are presented both without and with the inclusion of component loads to demonstrate the success of the presented methodology.
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